Apparatus for leaching tanbark.



Patented Apr. 29, i902.

G. C. VAUGHN. APPARATUS FOB LEACHING TANBA'RK.

(Applicntinn filed Aug. 5, 1898.):

2 Sheets-Sheet L (No Model.)

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Patented Apr. 29, |902.

G. C. VAUGHN.

APPARATUS FR LEACHING TANBARK.

(Application led Aug. 5, 189B.)

2-Sheets Sheet 2,

(No Model.)

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GEORGE C. VAUGHN, OF SALEM, MASSACHUSETTS, ASSIGNOR, BY MESNE AS- SIGNMENTS, TO VAUGHN MACHINE COMPANY, OF BOSTON, MASSACHU- SETTS, A CORPORATION OF WEST VIRGINIA.

APPARATUS FOR LEACHING T'ANBARK.

SPECIFICATION forming part of Letters Patent N o. 698,823?, dated April 29, 1902.

Application filed August 5, 1898.`

like characters on the drawings representing ro like parts.

This invention relates to a rotatable leaching apparatus especially adapted for leaching tanbark, and is an improvement-upon the invention shown and described'iu another I application, Serial No. 666,396, filed by me January 12, 1898.

My present invention has for its object to provide a rotatable leaching apparatus with which the leaching process may be carried o'n 2o more expeditiously and without liability of the outlet or outlets for the extractor percolated liquor becoming permanently clogged up or restricted in area by the iine tanbark.

AAnother feature of this invention consists in a novel heating apparatus withinthe leaching apparatusl whereby a more eficient,

heating o f the leaching liquor and tanbark may be effected.

These and other features of this invention 3o will be pointed out in the claims at the end of this specification. v Y v Figure l is a vertical longitudinal or axial section of a rotatable leaching apparatus em,-

bodying this invention; Fig. 2, a transverse section through one of the extract-outlets,`

taken on the line 4 4, Fig. l, and looking toward the right; Fig. 3, a similar section through the same extract-outlet, taken on thev line 3 3, Fig. l; Fig. 4, a transverse section 4o through the apparatus shown in Fig. 1', the

section being taken on the line 4 et looking in the direction of the Varrow thereon; and Fig. 5, a detail of the heating apparatus.

In the present instance I have shown this invention as embodied in a rotatable leaching apparatus-of thevsame general structure as that shown in the application above referred to and comprising a rotatable drum a, having hollow journals ct a2 and preferably provided with a partition-wall or false head a3,

which separates the drum into a leaching- `circumference of thedrum.

or screen referred to'is preferably made as Serial No. 687,869. (No model.)

chamber a4 and a liquor-chamberva. The leaching-chamber a4 is provided with preferably a plurality of separate outlets for the extract or percolated liquor and with lifting devices forthe tanbark, and in the present in-v stance said lifting devices forming side walls for the liquor-outlets. The leaching-chamber of* is provided, as herein shown, with sixseparate liquor-outlets a7,extended,as shown,lon gitudinally or axially of the said chamber and disposed about the inner circumference of the drum at substantially equal distances apart; but this number of outlets may be varied. In'the present instance the liquoroutlets al assume the forml of substantially trough-shaped channels'having side walls of am andclosed at the top 'by a strainer or screen and,'as shown, at the bottom by the The strainer herein shown, and consists of a series of substantially `V-shaped bars or slats 01.13,'of

lwood or other suitable material, extended the length of the outlet-passage, as herein shown, and secured to the side walls a9 al", as by bolts or stay-rods a, (see Fig. 3,) the said bars or slats being secured in position preferably with the base of the V outermost, so as to reducethe size of the entrance for the liquor into the'outlet-passage and obtain a better clearing or cleaning action of the extract liquor upon the strainer, as will be described. The strainer or screen is Ipreferably closed to the passage of the extract at suitable intervals by substantially V-shaped slats 'or bars d20, whicharev inserted between the slats or bars a, as shown in Fig. 3, and which lare held in place by the stay rods or bolts n.15. The bars or slatsfot2o serve to reinforce or strengthen the strainer or screen and prevent its warping under the influence of heat and moisture when made of Wood, which is preindicated by the distance between the points 10 l2, Fig. 1. The slats or bars 0.13 :may and preferably will be supported at their ends and at suitable points throughout their length by substantially archshaped cross-bars a2?. (See Figs. 1, 2, and 3.) The outlet-passages@7 in the present instance discharge into the chamber a5 through holes or openin gs c25 in the parferred. The length of the slats or bars d20 is partition-Wall.

'bark and leaching liquor.

tition-Wall a3, and the discharge-opening 0,25 for each liquor-outlet passage'is of less area than the area of the said passage and is preferably located at one side of the transverse center of the outlet-passage, as shown in Figs. 2 and 3, for a purpose as will be described.

The chamber c5 constitutes a liquor chamber or well, in which the extract liquor may accumulate and from which the said liquor may be discharged through the depending stationary leg Z9 of the liquor-outlet pipe Z9', extended through the hollow journal c2.

The leaching-chamber a4 is provided with a liquid-inlet, preferably a substantially large pipe b5, provided with perforations Z91 in its upper side and extended to near the partition- Wall a5, Where it is supported by a spider or frame Z95, bolted or otherwise attached to said Theliquor-inlet pipe Z95is stationary with relation to the drum, as herein shown, and is closed at its inner end by a suitable stopper or plug. Z911, through which loosely extends a steam-inlet pipe Z9?, which passes through the liquid-inlet pipe to the outside of the drum, as shown in Fig. I. The hollow journals a a2 are provided with suitable stuffing-boxes Z98 Z99 and are mounted to turn in suitable supports B B.

In the present instance the leaching-chamber contains the heating apparatus, which is closed to the passage of steam into theleaching-chamber, thereby avoiding dilution of the extract liquor, and the said heating apparatus is preferably made, as herein shown, so as to obtain a superior heatingof the tanrlhe heating apparatus is best shown in Fig. 5, and consists of a two-Way fitting Z910, provided with four mouths 2 3 4 5. The mouth 2 has connected to it the steam-inlet pipe Z9?, the mouths 3 4 pipes Z912 Z915, and the mouth 5 pipe Z914. The fitting Z910 is located close to the partition-Wal] a3, and the heating apparatus may be secured to said Wall in any suitable manner, as by straps Z950, so that the heating apparatus within the leaching-chamber may revolve With the drum. The pipes Z912 Z913are extended to near the circumferential Wall of the drum in substantially diametrically' opposite directions, e

branch pipes Z921 Z921, extended substantiallyv at right angles to each other and'parallel to the branch pipes Z916 Z915, the pipes Z920 Z921 being connected to a pipe Z925, extended longitudinally of the drum and joined to the pipe Z913. The pipe 514 is extended th rough the partition-wall and into a stuffing-box Z921 in the liquor-outlet pipe Z9', Where it meets or abuts p against a pipe Z925, extended through the said liquor-outlet pipe, the pipe Z925 constituting' the steam-outlet pipe for the heating apparatus. The steam-inlet pipe Z9? extends through the liquor-inlet pipe Z93 into a stuffing-box Z925, wherein it meets or abuts against a steamsupply pipe Z921. It will be seen that the steam-pipes Z97 Z911 are free to turn in the stuifing-boxes Z926 Z921, which construction permits the heating apparatus within theleachingchamber to revolve with the drum. The course of the steam through the heating apparatus may be traced as follows, viz: through the pipe Z97 to the fitting Z910, thence by the pipe Z912, branch pipes Z915 Z916, pipes Z918 Z919, branch pipes Z920 Z921, pipes Z922 Z913 to the fitting Z910, thence throughl the pipe Z911 and outletpipe Z925. It will thus vbe seen that the interior of the leaching-chamber is thoroughly heated and that the heat is well distributed throughout the contents of thechamber,which results in a more uniform and superior heating of the tanbark and leaching liquor, thereby quickening the leaching process.

The heating apparatus'referred to creates a steam-pressure Within the drum, and to prevent this pressure exceeding a predetermined point the drum may be provided With preferably a series of vent-openings normaliy closed by relief-valves of any suitable or desired construction, which may operate auto-` matically or which may be positively operated, Which latter method'of operating said valves is herein illustrated. In the present instance the vent-openings are made in the circumferential Wall of the liquor-chamber n.5, and each of said openings is controlled by a valve d, normally seated by a spring d', encircling its stem d2, which is extended outside of the'drum and, as shown, is adaptedin the revolution of the drum to meet an actuating device, shown as a bar (Z5, which acts in the nature of a cam to open the relief-valveand maintain it open until in the travel of the drum the valve-stem d2 is removed from engagement with said bar or cam, whereupon the spring d closes the valve.

The false head or partition-Wall CL3 may and preferably Will be provided with a suitable manhole normally closed by a door d10, (see Fig. 4,) through which access may be had to the liquor-chamber, and the leaching-chamber may be enteredthrough a suitable manhole in its circumferential wall, which is normally closed by a cover or door C312, and preferably said leaching-chamber Will be provided with two manholes substantially diametrically opposite.

In operation tanbark, preferably in a fine or comminuted'state, is placed in the leaching-chamber until the latter is preferaply substantially two-thirds full, and water or a weak leaching liquor is then admitted into said chamber through the liquor-inlet pipe a5, from which the said leaching liquor passes upward into the leaching-chamber through the perforations Z94 in said pipe and preferably lls the space above the mass or body of tanbark.

Steam is then circulated through the heating IOO IIO

apparatus and the drum is set in motion, which may be accomplished in any suitable` manner-as, for instance, by suitable chains, (not shown, but which are passed about the periphery of the drum.) The leaching liquor percolates down through the mass of tanbark, and the extract or percolated liquor passes through the strainer or screen of each outletpassage andin the construction herein shown Iiows through said passage into the yliquorchamber, from which it may be drawn off through the liquor-outlet pipe b' by a suitable pump, (not herein shown,) by means of which a continuous circulation of the leaching liquor throughthe tanbark is effected. As the drum revolves, for instance, in the direction indicated by arrow 40, Fig. 4, a portion of thelower part of the mass or body of the tanbark is carried up with the drum by the lifting devices, which in the present instanceV are the side walls a of the outlet-passages for the leaching-v chamber, and the bark thus lifted is carried abovel the upper surface of the mass of bark anddischarged upon the upper surface of the said mass, passing down through the body of leaching liquor which rests upon the mass of bark. As the lower portion .of the massof bark is elevated, as described, the mass or greater part of the bark descends by gravityr into position to have another portionlifted by the next lifting device. It will thus be A seen that the mass of tanbark is put in motion, so that all its particles are exposed to the action of the leaching liquor, while at the same time the greater portion of the bark is maintained in a compact form and presents a body of substantially uniform density, so that the leaching liquor percolates through the bark at a uniform rate, which results in a maximum extraction of the tannin matter in a minimum time ata minimum expense and with a uniform strength of extract liquor.

By reference to Fig. 4 it will be seen that the discharge-opening C625 for the liquor-outlet passage a7 is located at one side of the transverse center of said passage, which construction is preferred, as a substantially large amount of the extract or percolated liquor will remain in the outlet-passage a7 and will be discharged back into the leaching-chamber when the outlet-passage has been carried to a sufficient elevation. When the extract or percolated liquor is thus discharged back into the leaching-chamber, it passes througlr the screen or strainer in a reverse direction, and thereby washes the strainer clean and removes any of the fine bark which mightclog up the outlet-passage, so that when this outlet-passage is again broughtunder the mass of tanbark a free outlet is afforded for the extract. In otherwords, the outlet-passage f or the extract liquor is self-cleaning, and the V-shaped spaces between the bars or slats facilitate the cleaning action of the extract liquor discharged back into the leachingchamber.

I claiml. In a leaching apparatus,a rotatable drum having a partition-wall forming a leachingchamber and a liquor-chamber, and providedl with a liquid-inlet for the leaching-chamber and with a plurality of separate outlets locatedwithin the leaching-chamber' near the circumferential wall of the drum to move with the same and pass below the body of material being leached for the passage of extract or percolated liquor from said leaching-chamber into said liquor-chamber, strainers for said outlets affixed to the drum to pass below the said body of material, and means within vthe leaching-chamber to lift a portion of the material to be leached, substantially as described. y

2. In aleaching apparatus,a rotatable drum having a partition-wall forming a leachingchamber and a liquor-chamber, and provided with a liquid-inlet for said leaching-chamber, and with a plurality of separate outlets located within the leaching-chamber near the circumferential wall of the drum to move with I the same and pass below the body of material being leached for the passage of extract or percolated liquor from said leaching-chamber into said liquor-chamber, strainers for said outlets affixed to the drum to pass below the said body of material, means within the leaching-chamber to lift a portion of the material to be leached, and a heating apparatus within said leaching-chamber, substantially as described.

3. In a leachingapparatus,a rotatable dru-m to containl the material to be leached, provided too with'a liquid-inlet, and with a liquid-outlet passage havin-g side walls projecting inwardly from the inner circumference of the drumfand having a discharge-opening for the ,extract from said passage, and a strainer covering said outlet-passage, substantially as described.

4:. In a leaching apparatus,arotatable drum to contain the material to be leached provided near its inner circumference with an outletpassage for. the extract liquorextended .longitudinally of the drum and provided with an inlet for the extract from the drum and with Y a discharge-.opening for the extract from-said passage, a strainer covering the said inlet,

and means withinthe drum for lifting a portion of the material to be leached, substantially as described.

5. In a leaching apparatus,a rotatable drum provided with a partition-wall forming aleaching-chamber and a liquor-chamber, and hav- IIO IIS

ing an outlet-passage for the extract from the leaching-chamberv into the liquor-chamber, extended longitudinally of said drumwithin said leaching-chamber, a strainer for said outlet-passage, and a liquor-outlet for said liqucr-chamber, substantially as described.

6. In a leaching apparatus,a rotatable drum having a partition-wall forming a leachingchamber and a liquor-chamber, and provided with a liquid-inlet for the leaching-chamber,

and with-an outlet for the extract liquor into the liquor-chamber near the circumference of the drum, and a heating apparatus within the leaching-chamber attached to the drum to revolve therewith and comprising.,r a steam-inlet pipe Z2?, a fitting Z910, pipes Z112, Z213 connected to said fitting and extended in substantially opposite directions toward the'circu'rnference of the drum, branch pipes 61"", Z216, Z920, Z221 extended substantially at right angles near the opposite ends of the leaching-chamber, pipes Z115, Z919 extended longitudinally of the drum and connecting said branch pipes together, the pipe Z322 connecting` the branch pipes bw, Z221, to the pipe Z913, and the outlet-pipe Z914 connected to the said fitting, substantially as described.

7. Inaleachingapparatus,arotatable drum to contain the material to be leached, provided with a liquid-inlet, and with a liquid-outlet passage for the extract having side walls projecting inwardly from the inner circumference of the drum and having a dischargeopening for the extract, and a strainer for' said outlet-passage composed of a series of bars or slats, substantially as described.

S. Inaleachingapparatus,a rotatable drum to contain the material to be leached provided With a liquid-inlet and With a plurality of separate outlets for the extract liquorlocated Within the said drum to pass below the mass or body of material being leache'd and provided With discharge-openings for the extract from said passages, strainers covering said outlets, and means Within the drum to lift a portion of the material to be leached, substantially as described.

' In testimony whereof I have signed my name tothis specification in the presence of two subscribing Witnesses.

GEORGE C. VAUGHN.

Vitnesses:

JAS. H. CHURCHILL, J. MURPHY. 

